1. 这是个什么词？
词：optimal
英英释义：the best or most suitable for a particular purpose or in a particular situation
例句：Although some British universities require a minimum IELTS score of 6.5 for admission, 7.5 would be optimal for those who want to have an edge.
2. 为什么选这个词？
“optimal”是形容词，意思是“最优的、最理想的”。有时它还可以拼写作 optimum，意思和用法不变。一般 optimal 可以用来形容时机、条件、解决方案、结果等，常可以替换 best 和 ideal。这个词在《经济学人》中出现的频率非常高，我们在口语和写作中都可以使用。下面来看几个例子。
虽然有的英国大学录取要求是雅思 6.5 分，但 7.5 分更容易被录取，我们就可以说：
Although some British universities require a minimum IELTS score of 6.5 for admission, 7.5 would be optimal for those who want to have an edge.
有些户型不是方方正正的，实用面积有限，如果室内设计巧妙，充分利用了空间，我们就可以说：
This interior design makes the optimal use of the available space.
最优的解决方案应该是用最少的预算和时间完成项目，就可以说：
The optimal solution is to use as little budget and time as possible to get the project done.
《经济学人》最近在一篇应对气候变化的文章中就用到了 optimal:
A carbon price is indeed the optimal way to reduce pollution, but getting people to pay for carbon has been a vote-loser in America and Europe.
另一篇关于新能源的《经济学人》文章中也出现了 optimal:
SkySails’ kite is launched, like a recreational kite, into the wind at ground level. Then, as the kite is pulled up by the wind while being manipulated to travel in a series of figures-of-eight in order to achieve a constant, optimal speed, the tether uncoils, spinning the drum.
《经济学人》在写美国对含糖饮料征税的文章中多次用到了 optimal, 比如下面两句：
They compute an optimal tax rate of 1-2 cents per ounce of soft drink in America. Taking this into account they reckon that the optimal rate for cities is 0.5 cents, although a more efficient system would be a state or national tax to control America’s sugar rush.
3. 怎样学会使用这个词？
1）翻译下面的句子： 一些应用更多关心的是最佳用户体验，而不是不顾一切的增长。
Some apps are more concerned about ensuring optimal user experience than pursuing relentless growth.
（参考翻译：Some apps are more concerned about ensuring optimal user experience than pursuing relentless growth.)
2）结合自己的生活、学习、工作、兴趣等，想象在什么语境下会用到这个表达。先简要描述这个场景，再造句。
例子： 按时吃药以达到最佳的疗效。
场景：Take medicine duly to achieve the optimal efficacy.